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#ifndef HEURISTIC_H
#define HEURISTIC_H

#include <tuw_global_router/srr_utils.h>

namespace multi_robot_router
{
class Heuristic
{
  public:
    /**
             * @brief calculates the euclidean distance to the end vertex
             * @param _next the current vertex the heuristic is calculated for
             * @param _end the goal vertex for calculations
             * @returns the euclidean distance to the goal
             */
    float calcHeuristic(const Vertex &_next, const Vertex &_end) const
    {
        float nx = (_next.getSegment().getStart()[0] + _next.getSegment().getEnd()[0]) / 2;
        float ny = (_next.getSegment().getStart()[1] + _next.getSegment().getEnd()[1]) / 2;

        float ex = (_end.getSegment().getStart()[0] + _end.getSegment().getEnd()[0]) / 2;
        float ey = (_end.getSegment().getStart()[1] + _end.getSegment().getEnd()[1]) / 2;

        float dx = (nx - ex);
        float dy = (ny - ey);

        return std::sqrt(dx * dx + dy * dy);

        //return 0; //Dijkstra expansion
    }
};
} // namespace multi_robot_router

#endif // HEURISTIC_H
